Discover Digital Clarity Advanced D.sound technology is comprised of four components that work together to elevate your audio experience to the next level. A digital amplifier helps reduce distortion and also helps you achieve crystal-clear sound -- even at higher volume levels. The S-XBS and Digital Audio Gain Control help to improve bass response at higher volume levels and MP3 Re-Master technology allows you to receive outstanding sound quality from compressed music files, such as MP3. Long, Smooth Playback You can achieve up to 140 hours of MP3 and up to 80 hours of CD-DA playback with the supplied external battery case. It lets you power the unit with two Ni-MH rechargeable batteries and two AA alkaline batteries, for some amazing playback times. The SLCT720 is designed to reduce or eliminate CD skipping during most active uses. There is even a backup memory feature that helps provide further assurance of a skip-free listening experience. Plays MP3 Files MP3 is the most popular and widely used digital audio compression format available today. Since MP3 files are so small, you can burn a library of music onto CD-R/RWs froma compatible computer and play them back on your SLCT720. And with ID3 Tagging, you can display the title, artist name and album on the remote while the MP3 file is playing. Packs Punch In A Small Package The SLCD720 portable CD player has the power to deliver audio that defies its size. This handy little player is under an inch thick and weighs a mere 5.4 ounces without the battery. You'll hardly notice it during your busy day, but you'll sure be glad you have it with you.